Make eth_accounts return impersonated accounts (#5734)

* Return impersonated accounts

* Return unique accounts in deterministic order

crates/anvil/src/eth/api.rs

@@ -67,7 +67,7 @@ use foundry_evm::{
 };
 use futures::channel::mpsc::Receiver;
 use parking_lot::RwLock;
-use std::{sync::Arc, time::Duration};
+use std::{collections::HashSet, sync::Arc, time::Duration};
 use tracing::{trace, warn};
 
 use super::{backend::mem::BlockRequest, sign::build_typed_transaction};
@@ -528,10 +528,18 @@ impl EthApi {
     /// Handler for ETH RPC call: `eth_accounts`
     pub fn accounts(&self) -> Result<Vec<Address>> {
         node_info!("eth_accounts");
+        let mut unique = HashSet::new();
         let mut accounts = Vec::new();
         for signer in self.signers.iter() {
-            accounts.append(&mut signer.accounts());
+            accounts.extend(signer.accounts().into_iter().filter(|acc| unique.insert(*acc)));
         }
+        accounts.extend(
+            self.backend
+                .cheats()
+                .impersonated_accounts()
+                .into_iter()
+                .filter(|acc| unique.insert(*acc)),
+        );
         Ok(accounts)
     }
 

crates/anvil/src/eth/backend/cheats.rs

@@ -60,6 +60,11 @@ impl CheatsManager {
         trace!(target: "cheats", "Auto impersonation set to {:?}", enabled);
         self.state.write().auto_impersonate_accounts = enabled
     }
+
+    /// Returns all accounts that are currently being impersonated.
+    pub fn impersonated_accounts(&self) -> HashSet<Address> {
+        self.state.read().impersonated_accounts.clone()
+    }
 }
 
 /// Container type for all the state variables

crates/anvil/tests/it/anvil_api.rs

@@ -82,6 +82,7 @@ async fn can_impersonate_account() {
     res.unwrap_err();
 
     api.anvil_impersonate_account(impersonate).await.unwrap();
+    assert!(api.accounts().unwrap().contains(&impersonate));
 
     let res = provider.send_transaction(tx.clone(), None).await.unwrap().await.unwrap().unwrap();
     assert_eq!(res.from, impersonate);